Growth and nutrition of peanut crop subjected to saline stress and organomineral fertilization

ABSTRACT The peanut crop, owing to its microbiological and nutritional aspects, is of great economic importance for agriculture and the food industry. However, salt stress can negatively affect nutrient uptake and plant growth. The objective of this study was to evaluate the growth and foliar nutrient concentrations of peanut plants subjected to irrigation with saline water and different forms of organomineral fertilization. The experiment was conducted in a greenhouse in a completely randomized design (5 × 2 factorial scheme) with five forms of fertilization (F1 = 100% mineral; F2 = 100% bovine biofertilizer; F3 = 100% vegetal ash; F4 = 50% mineral + 50% bovine biofertilizer; and F5 = 50% mineral + 50% vegetal ash), two levels of electrical conductivity of the irrigation water (ECw) (1.0 and 5.0 dS m-1), and five replicates. Salt stress inhibited plant growth and the number of leaves, but increased the average stem diameter with the use of 100% bovine biofertilizer and higher salinity water. When ECw of 5.0 dS m-1 was used along with the bovine biofertilizer (100%), the P concentration in plants increased. The K concentration was reduced in plants fertilized with bovine biofertilizer (100%) and vegetal ash (100%), while Mg concertation was reduced in plants fertilized with bovine biofertilizer (100%) or mineral fertilizer (50%) + bovine biofertilizer (50%) with irrigation water of 5.0 dS m-1. RESUMO A cultura do amendoim em razão dos aspectos microbiológicos e nutricionais torna-se uma cultura de grande importância econômica para agricultura e indústria alimentícia. No entanto, o estresse salino pode causar efeitos negativos na absorção de nutrientes e no crescimento de plantas. Objetivou-se avaliar o crescimento e os teores foliares de nutrientes de plantas de amendoim submetidas a irrigação com água salina e formas de adubação organomineral. O experimento foi conduzido em casa de vegetação, em delineamento inteiramente casualizado, no esquema fatorial 5 × 2, referente a cinco formas de adubação (F1 = 100% mineral, F2 = 100% biofertilizante bovino, F3 = 100% cinza vegetal, F4 = 50% mineral + 50% biofertilizante bovino e F5 = 50% mineral + 50% cinza vegetal) e dois valores de condutividade elétrica da água de irrigação (1,0 e 5,0 dS m-1), com cinco repetições. O estresse salino inibiu a altura da planta e o número de folhas, mas aumentou o diâmetro médio do caule com utilização de 100% de biofertilizante. As adubações com fertilizante 100% mineral, 100% b